package com.study.algorithm.binarytree;

//  TreeNode 类
public class TreeNode {
    int val;
    TreeNode left;    // 必须有 left 字段
    TreeNode right;   // 必须有 right 字段

    TreeNode() {
    }

    TreeNode(int val) {
        this.val = val;
    }

    TreeNode(int val, TreeNode left, TreeNode right) {
        this.val = val;
        this.left = left;
        this.right = right;
    }
}